1. Field of the Invention
The present invention relates to a switched telecommunications network, and to a method of transmitting data through a switched network.
2. Related Art
Dedicated networks for the transmission of different types of data are known. For example, the public switched telephone network (PSTN) provides voice data communications over well-established international channels. In addition, networks are becoming increasingly available which are capable of switching other types of traffic, such as computer originating data and video data. Local exchanges are provided for each of these types of data, and the user is provided with a dedicated local line, connecting the user's terminal equipment to said exchanges.
The cost of transmitting data through networks, particularly when such networks cover wide geographical areas, is largely dependent upon the level of bandwidth required by the application. Bandwidth requirements may be reduced by implementing compression algorithms. However, compression becomes extremely lossy if de-compression followed by further compression is repeated many times in order to effect transmission through the network.